I remember EMS and XMS being called “expanded memory” and “extended memory,” but I’m not clear on what the difference really is, so I wanted to ask. Is there any detailed documentation?
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中国DOS联盟论坛 » DOS学习入门 & 精彩文章 （教学室） » What’s the difference between EMS and XMS?
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Posted 2005-03-27 00:00 · 中国 上海 长宁区 电信
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Posted 2005-03-29 00:00 · 中国 广东 广州 教育网
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Older DOS programs need EMS, limited to 32MB
EMS came first, then XMS
EMS came first, then XMS
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Posted 2005-08-08 02:05 · 中国 广东 广州 越秀区 电信
Originally posted by GOTOmsdos at 2005-3-29 00:00:
Older DOS programs need EMS, limited to 32MB
EMS came first, then XMS
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Posted 2005-08-09 20:31 · IANA 局域网IP(Private-Use)
EMS is read using page mapping, and when reading or writing EMS it still needs to occupy part of the low address space.
That’s why if emm386 is used with the ram parameter, the available conventional memory decreases. So I usually use the noems parameter.
That’s why if emm386 is used with the ram parameter, the available conventional memory decreases. So I usually use the noems parameter.
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Posted 2005-08-11 13:41 · 中国 香港
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Originally posted by Greentea at 2005-3-27 12:00 AM:
I remember EMS and XMS being called “expanded memory” and “extended memory,” but I’m not clear on what the difference really is, so I wanted to ask. Is there any detailed documentation?
Extend requires Protectd Mode, needs a 286 or above, direct linear access, there is no such thing as "paging"
Expand only needs Real Mode, even an 8086 can use it, it divides memory into 64K "pages", and uses pages for access
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Posted 2007-06-16 17:38 · 中国 江西 南昌 电信
Seems like you got it backwards, right? XMS came first and then EMS.
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